oractical 2:pt 1

What is the nasal cavity?

The hollow space inside the nose where air enters. It warms, humidifies, filters incoming air, and contains smell receptors.

What is the nasal septum?

The wall that divides the nasal cavity into right and left sides. It is formed by the perpendicular plate of the ethmoid, vomer, and septal cartilage.

What are the external nares?

The nostrils that allow air to enter and leave the nasal cavity.

What are the internal nares (choanae)?

Openings at the back of the nasal cavity that connect to the nasopharynx.

What are the superior nasal conchae?

The smallest nasal conchae located near the roof of the nasal cavity. They help create airflow turbulence and are close to the olfactory region.

What are the middle nasal conchae?

Curved bony shelves that increase surface area to warm, humidify, and filter inhaled air.

What are the inferior nasal conchae?

The largest nasal conchae and separate bones. They perform most of the warming, humidifying, and filtering of inhaled air.

What are the nasal meatuses?

Air passages beneath each concha that allow airflow and drainage from the paranasal sinuses.

What is the olfactory epithelium?

Specialized tissue in the roof of the nasal cavity that contains smell receptors.

What are the paranasal sinuses?

Air-filled cavities in the skull that produce mucus, lighten the skull, warm air, and add resonance to the voice.

What is respiratory mucosa?

Pseudostratified ciliated columnar epithelium with goblet cells that traps particles and moves mucus toward the throat.

What is the function of goblet cells?

Goblet cells secrete mucus that traps dust, bacteria, and other particles entering the respiratory tract.

What is the function of cilia?

Tiny hair-like structures that move mucus and trapped debris toward the pharynx to keep the airways clean.

What is the pharynx?

A muscular passageway for both air and food that connects the nasal and oral cavities to the larynx and esophagus.

What is the nasopharynx?

The upper region of the pharynx behind the nasal cavity. It carries only air and contains the pharyngeal tonsil and auditory tube openings.

What is the oropharynx?

The middle part of the pharynx behind the mouth. It serves as a passageway for both food and air.

What is the laryngopharynx?

The lowest part of the pharynx where food continues to the esophagus and air enters the larynx.

What is the pharyngeal tonsil (adenoid)?

Lymphoid tissue in the nasopharynx that helps defend against inhaled pathogens.

What are the palatine tonsils?

Paired tonsils located on each side of the oropharynx that help fight infections entering through the mouth.

What are the lingual tonsils?

Lymphoid tissue located at the base of the tongue that helps protect against pathogens.

What are the auditory (Eustachian) tubes?

Tubes connecting the middle ear to the nasopharynx to equalize air pressure.

What is the larynx?

The voice box located between the pharynx and trachea. It protects the airway and contains the vocal cords.

What is the thyroid cartilage?

The largest cartilage of the larynx that forms the Adam's apple and protects the vocal cords.

What is the cricoid cartilage?

The only complete ring of cartilage around the airway that supports the larynx.

What is the epiglottis?

A flap of elastic cartilage that covers the larynx during swallowing to prevent food from entering the trachea.

What is the glottis?

The opening between the true vocal cords where air passes during breathing and speech.

What are the true vocal cords?

Folds of tissue that vibrate to produce sound.

What are the false vocal cords (vestibular folds)?

Folds located above the true vocal cords that help protect the airway but normally do not produce sound.

What is the hyoid bone?

A U-shaped bone that supports the tongue and larynx. It is the only bone that does not articulate with another bone.

What is the trachea?

A tube connecting the larynx to the bronchi. It carries air to and from the lungs.

What are the C-shaped tracheal cartilages?

Rings of hyaline cartilage that keep the trachea open while allowing the esophagus to expand during swallowing.

What is the trachealis muscle?

Smooth muscle on the back of the trachea that narrows the airway during coughing.

What is the carina?

The ridge where the trachea divides into the right and left primary bronchi. It is highly sensitive and triggers the cough reflex.

What is the bronchial tree?

The branching system of airways that carries air from the trachea to the alveoli.

What are the primary bronchi?

The first branches of the trachea that enter each lung. The right bronchus is wider, shorter, and more vertical.

Why do inhaled foreign objects usually enter the right lung?

Because the right primary bronchus is wider, shorter, and more vertical than the left.

What are the secondary (lobar) bronchi?

Branches of the primary bronchi that supply each lobe of the lungs.

What are the tertiary (segmental) bronchi?

Branches of the secondary bronchi that supply individual bronchopulmonary segments.

What are bronchioles?

Small airways that lack cartilage and regulate airflow through smooth muscle.

What are terminal bronchioles?

The last part of the conducting zone. They conduct air but do not participate in gas exchange.

What are respiratory bronchioles?

The first part of the respiratory zone where gas exchange begins.

What are alveolar ducts?

Small passages that lead from respiratory bronchioles to alveolar sacs.

What are alveolar sacs?

Clusters of alveoli that increase the surface area for gas exchange.

What are alveoli?

Tiny air sacs where oxygen diffuses into the blood and carbon dioxide diffuses into the lungs to be exhaled.